Zim being nonbinary and totally not giving a shit about Earth’s wacky gender roles. Like “Hmm… These sparkly high-heeled shoes would make me look even more intimidating than I already am!” Then you get those shoes, you adorable bug-eyed creep. They look great on you.
Zim discovering Lisa Frank stickers thanks to Gir bringing them home or something and becoming obsessed with them. He puts his favorites on his PAK. Dib makes fun of him for it at first but then he starts helping Zim collect them.
Trans boy Dib!! Zim catching a glimpse of Dib’s binder when they’re changing for gym or something and cautiously asking him what that “weird vest thing” is all about. Dib doesn’t really know how to explain it so he just kind of shrugs and says “some earth boys wear these” and Zim just kind of goes “oh” and accepts it without a second thought.